The content of the measurement range and measurement rate of a digital multimeter
measuring range
In a multifunctional digital multimeter, different functions have corresponding maximum and minimum values that can be measured.
Measurement rate
The number of times a digital multimeter measures the amount of electricity being measured per second is called the measurement rate, and its unit is "times/s.". It mainly depends on the conversion rate of the A/D converter. Some handheld digital multimeters use measurement cycles to indicate the speed of measurement. The time required to complete a measurement process is called the measurement cycle.
There is a contradiction between measurement rate and accuracy indicators, usually the higher the accuracy, the lower the measurement rate, and it is difficult to balance the two. To solve this contradiction, different display digits or measurement speed conversion switches can be set on the same multimeter: a fast measurement gear can be added, which is used for A/D converters with faster measurement speeds; By reducing the number of display digits, the measurement rate can be significantly improved. This method is commonly used and can meet the needs of different users for measurement rate.
Usage precautions
1. Before using a multimeter, a mechanical zero adjustment should be performed, which means that when there is no measured electricity, the pointer of the multimeter should be placed at zero voltage or zero current.
2. During the use of a multimeter, do not touch the metal part of the probe with your hands. This not only ensures accurate measurement, but also ensures personal safety.
3. When measuring a certain amount of electricity, it is not advisable to shift gears simultaneously, especially when measuring high voltage or high current. Otherwise, it will damage the multimeter. If you need to shift gears, you should first disconnect the probes and then take measurements after shifting gears.
4. The multimeter must be placed horizontally during use to avoid errors. At the same time, attention should also be paid to avoiding the influence of external magnetic fields on the multimeter.
5. After using the multimeter, the conversion switch should be placed at the maximum AC voltage level. If not used for a long time, the battery inside the multimeter should also be removed to prevent the battery from corroding other components inside the meter.
